Does anyone know how long it should take to drive from the park to his house at 3AM? He arrived in 8 minutes from Lyft dropoff. This seems pretty fast to me, if he attacked her in a premeditated manner in the car. Not enough time for a struggle. Also, if he attacked her in the car, I would think he would have gone straight to dispose of the body, not to his house right off. This leads me to believe she made it to the house. I also believe AA's ultimate purpose and goal with ML was sex and control. Under his terms. In his house.
I do think somewhere along the way, ML rejected him. At the house. Or even during the car ride. Maybe she asked to get out of the car and things went down from there. ML may have gotten the vibe that AA was not who he was pretending to be and that she was in danger. This was not part of AA's plan, and he snapped. Maybe she ran and tried to escape from the house. And she made it to the door trying to get out and that's why they are examining the doors?
Given his profile, I bet AA has always considered killing in the back of his mind, if he doesn't get what he wants. I wouldn't be surprised if he routinely went to his dates/encounters ready to kill if he needs to. Another woman reported that he insisted first on picking her up. When she refused, he insisted they meet in a public parking lot and then get into his car to go on the date. When she refused, he lost his sh** verbally. I believe this is why he met ML at the park. This is what AA does to maintain the power and control he wants. He intentionally tries to look "safe" by suggesting a "public" meeting place. The woman will have no car at his house and can't escape/just leave on her own terms.
Perhaps he routinely carried items in the car he would need to attack if the moment presented himself. If he didn't purchase the zip ties after he killed her, (we only heard about a gas can), we know he had quick access to zip ties in his home. Therefore, AA may only comfortable in his house and in his car. No way he was going to have another rape accusation if a woman refused his advances.
R.I.P. Mackenzie.
All pure speculation on my part.